undo does not unload file, enum for different player statuses
add toggle input parameter function
Merge branch 'master' of https://github.com/bennettslin/AudioPeeps into bennettslin-master

Conflicts:
	AudioPeeps/PSAudioEditor.h
	AudioPeeps/PSAudioEditor.m
	AudioPeeps/PSAudioVC.m
	AudioPeeps/PSAudioVC.xib
commit after merge